The hike begins at the car park in front of the main gate of the Domaine de Rentilly, Route de Guermantes (D217b) in Bussy-Saint-Martin.
(S/E) Enter the park and, after studying the map to familiarise yourself with the layout of the different areas, turn left onto the path towards the Grille de la Brosse. It runs roughly parallel to the Route de Guermantes.
(1) At the Grille de la Brosse, turn right towards the château (a square post bears directions).
(2) Go around the castle, passing in front of the main façade, then follow the ponds until you reach the third lane.
(3) Turn right and go down a few steps. Continue and turn right at the next intersection, then left into the lane at the corner of a grassy retention pond. Two hundred metres further on, turn right and continue towards the Grille des Gardes.
(4) Turn left into the lane closest to the one you have just left. It goes back up into the woods. Follow it to the park fence, where it turns left into a rectangular clearing.
Take the first lane on your right. It ends at the lane surrounding the French garden. Turn right and, after going about a quarter of the way around the statue, turn right onto the path that leads to the park's Black Gate.
(5) Leave the park. Cross the moat bridge, turn left at the Rond-Point de la Grille Noire, cross Rue de l'Etang and, a few metres further on, turn left onto the path leading to the Vallée de la Brosse (signpost). After a left turn near a white metal cross, this road arrives at the edge of a housing estate. Continue along Chemin de la Croix Blanche.
(6) After passing through the gate, turn right onto Chemin de l'Etang de la Broce (see sign on the post).
At the roundabout, take the wide tree-lined lane closed off by low walls forming chicanes. Follow the path on the right; it curves to the right.
(7) Pass along the Etang de la Broce. When the path reaches a junction with several paths, continue in the centre on the widest one, which climbs the slope towards industrial buildings whose roofs are visible. You will reach a car park near the RER railway line.
(8) Turn left onto the path that starts with a footbridge and heads towards the Etang de la Broce (signpost).
This path descends. At the next crossroads, continue towards the Etang de la Loy (signpost) and continue downhill. The path winds along the Ru de la Brosse, which you cross on a bridge on your right. Then take the path immediately on your left and cross the stream again a little further on the left.
Continue to the D217b. Cross the road and continue opposite towards the Etang de la Loy, using the path for horse riders. When you reach a fork where a signpost indicates right for horse riders and left for cyclists, take the path for horse riders to get closer to the bank of the Etang de la Loy.
(9) At the crossroads, take the path on the left that crosses the dam. This will take you to the edge of a housing estate where a signpost at the first crossroads indicates the direction of the Parc Culturel de Rentilly. Do not turn, but continue straight ahead until you reach a very large tree-lined avenue, which you take on the left (a signpost also indicates the direction of the Parc Culturel de Rentilly).
(10) Continue. At the end of this lane is the car park (S/E).